Anthony Zettel and Cornelius Washington took first-team reps at end most of the summer, and rookies Alex Barrett, Jeremiah Valoaga and Patrick O'Connor were competing for backup jobs.

Ansah had just two sacks in 13 games last year, when he was hampered by a high-ankle injury much of the season. In 2015, he made the Pro Bowl with 14.5 sacks.

Lions coach Jim Caldwell said this week that he expects Ansah to have some rust when he returns to the field.

"Anytime that you miss a lengthy portion of time during preseason, it takes a while to get back," Caldwell said. "It’s just not a sport where you jump back in. It’s rare, I should say. It’s not impossible, but it’s rare that a guy comes back and he is where he’ll be two, three weeks down the road."

Along with Ansah, the Lions activated backup offensive tackle Corey Robinson from the physically unable to perform list following off-season foot surgery.

Robinson is expected to serve as the Lions' swing tackle once he's ready for action. He appeared in 14 games and made three starts last year.